Powered panel moving system

ABSTRACT

A powered panel moving system includes a motor, electronic drive circuitry, mechanics, a coupler, and electronic anti-entrapment circuitry. The drive circuitry drives a rotor of the motor such that the rotor has a rotational output in response to being driven. The mechanics moves a panel upon being driven. The coupler couples the rotational output of the rotor to the mechanics in order drive the mechanics for the mechanics to move the panel. The anti-entrapment circuitry controls the drive circuitry to prevent the panel from entrapping an object. The drive circuitry drives the motor based on measurements indicative of at least one of motor current, motor speed, and panel position. The drive circuitry and the anti-entrapment circuitry are integrated with one another such that the anti-entrapment circuitry controls the drive circuitry based on the same measurements.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. application Ser. No.11/079,016, filed Mar. 11, 2005, which is hereby incorporated byreference in its entirety.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention generally relates to powered panel moving systemsand, more particularly, to a powered panel moving system havingelectronic function circuitry integrated with electronic motor drivecircuitry for providing additional functionality beyond driving a motorfor movement of a panel.

2. Background Art

Standard automotive power window systems employ a brush type directcurrent (DC) motor with reduction gearing and suitable rotary-to-linearmotion transformation fixtures to enable the motor to raise and lower awindow. The requirement to drive the window completely into acompressible weather seal upon closing and withdraw the window uponopening can lead to forces driving the window having a magnitude of manyNewtons (N).

Suitable fixtures for converting motor torque into the required closureforce include cable systems, worm gears, planetary gears, and rack andpinion gearing systems, and the like. A typical fixture uses a gearsystem such as planetary gears to convert an approximately 3,000 rpmmotor speed at approximately 0.4 Nm torque to an output rotation of 120rpm at 10 Nm for a 3000/120=25:1 torque multiplication and speedreduction. The 120 rpm output is then converted to linear motion todrive a window with near stall forces of up to 450 N or more andunobstructed speeds of up to 11 inch/sec or more.

Unfortunately, a force having a magnitude of more than 100 N issufficient to cause injury when a human body part become entrapped in awindow being closed by this force. Techniques used to prevent suchinjury include placing a sensor in the closure region of the window suchas described in U.S. Pat. No. 6,782,759. This has the disadvantage ofrequiring the sensor.

Another common approach is to monitor for either motor stall current ora rapid rise in motor current caused by the window hitting anobstruction. The motor is then reversed. However, reversal on motorcurrent sensing allows a significant fraction of the window closureforce to be applied to the obstruction if the obstruction is a softobject such as a child's neck. Soft obstructions can be sensed via motorcurrent sensing if motor speed and/or window position are also measuredas described in U.S. Pat. No. 6,064,165. This has the disadvantage ofrequiring additional speed and/or window position sensors.

It is well known to those skilled in the art of employing electricmotors that the torque developed by a DC motor is generally a functionof its size and the current it draws. The power of a DC motor is afunction of the drive voltage, number of armature turns, and the appliedcurrent. A primary design trade that is made in motor applications is inmotor size. For comparable input drive voltages and currents, a largerDC motor produces more torque than a smaller DC motor. However, asmaller DC motor can have approximately the same rated power as a largerDC motor for approximately the same input voltage and current, but willhave it at a higher speed and lower torque. A smaller motor also hasless surface area and mass. This can result in higher temperatureoperation for a smaller motor running at the same drive voltage andpower of a larger motor. As much of the heating is caused by I² R lossesin the armature winding, a way to mitigate this problem is to use asmaller gauge wire and add windings and then operate at a highervoltage. However, many DC applications such as automotive applicationshave limitations in drive voltage. This causes all motor choices to workwithin a fixed drive voltage.

A second design trade is in terms of DC motor type. Conventional brushtype DC motors have an armature wound on a rotor of the motor. This canlimit the power rating of the motor as the armature can dissipate heatfrom the load current only through its shaft and bearings and heatrejection to air inside the motor case. In an alternative design, mostcommonly used on DC brush-less motors, the armature winding is moved tothe stator with the rotor equipped with permanent magnets. This has theadvantage of allowing the armature windings to be heat sunk directly tothe motor frame. Then within the limitations of the heat sink providedto the motor frame, the motor can in some cases be run at highercurrents than a comparable sized motor with internal armature windings.

A smaller motor offers a primary advantage in terms of the cost of itsmaterials and the reduced weight and volume it takes up within a systemit is powering. However, the design choice of a smaller motor hasdisadvantages. To match the power output of a larger motor, a smallermotor operates at higher speed. This offers at least four designchallenges.

The first design challenge is that higher speed operation reduces theuseful life of any brushes that are used. The second design challenge isthat a more extreme “gear reduction”/“mechanical advantage” ratio isrequired to recover the equivalent torque that would be obtained from alarger motor at the same power rating. For instance, a motor operatingat 3,000 rpm with 0.4 Nm torque requires a 25:1 gear ratio to get to atarget 120 rpm at 10 Nm. However, a smaller 30,000 rpm motor with 0.04Nm torque requires a 250:1 reduction gear ratio to match to the sametarget 120 rpm at 10 Nm. This could cause more wear and acousticemissions than experienced with the lower gear ratio operating at lowermotor speed. The third design challenge is that human hearingsensitivity is lower at the 50 Hz of a 3,000 rpm motor than at the 500Hz of a 30,000 pm motor, resulting in the higher speed motor presentinga higher audio profile than would a larger, slower motor.

The fourth design challenge is in matching the motor to the mechanicalcoupling means used to match the motor's mechanical output to whatevercomponent the motor is intended to move, e.g., an automotive powerwindow or panel. Motors can be mounted on and move with the component orcan be mounted to the structure on which the component moves. Gearingcan be used to provide mechanical advantage such as in the employment ofplanetary gears and even gearbox transmissions as described in U.S. Pat.No. 6,515,399. Often gearing is used in combination with levers such asin the “arm and sector” configuration commonly used in automotive powerwindow applications and described in U.S. Pat. No. 6,288,464 or in arack and pinion configuration.

Flexible drive components such as cables (described in U.S. Pat. No.4,186,524), tapes (described in U.S. Pat. No. 4,672,771), chains, andbelts can be employed as well. In systems with the motor on the movablecomponent, a worm gear, toothed track or slotted track, can be mountedon the stationary structure and be used to drive the motor and thecomponent through the desired range of motion. Additionally, the motorscan be applied to pumps to drive pneumatic or hydraulic pistons toaffect the desired component motion. Clutches as described in U.S. Pat.No. 6,288,464 and brakes as described in U.S. Pat. No. 6,320,335 can beemployed in combination with the mechanisms here described to engage ordisengage torques and forces and/or to lock motion.

In the case of power windows and panels, the motor and mechanicalcoupling can be used to affect a linear or rotational sliding motion ofthe subject component or can be used to drive a hinged motion. Othermotion types and mechanical coupling means are possible.

The problem of brush wear can be addressed by using a brush-less DCmotor design. However, this introduces more cost via the additionalelectronics required for brush-less operation.

SUMMARY OF THE INVENTION

Accordingly, it is an object of the present invention to provide apowered panel moving system having electronic function circuitryintegrated with electronic motor drive circuitry for providingadditional functionality beyond driving a motor for movement of a panel.

It is another object of the present invention to provide a powered panelmoving system having entrapment detection circuitry integrated withbrush-less motor drive circuitry such that motor current, motorposition, motor speed, and panel position measurements can be shared andused by both the entrapment detection circuitry and the brush-less motordrive circuitry.

It is a further object of the present invention to provide a poweredpanel moving system having powered panel control circuitry, entrapmentdetection circuitry, and brush-less motor drive circuitry integratedwith one another such that a single controller can use powered panelcontrol functions with entrapment detection functions and/or brush-lessmotor driving functions.

It is still another object of the present invention to provide a poweredpanel moving system having a small, high-speed motor configured with ahigher mechanical advantage than used with a larger, low-speed motorsuch that cost savings from the resulting reduction in motor materialsaccommodates the cost of brush-less electronics used for the small,high-speed motor.

It is still a further object of the present invention to provide apowered panel moving system which is configured with a high-speedbrush-less DC motor driving a high mechanical advantage reduction gearsystem in order to produce the torque and speed combination of a largermotor that would otherwise be required.

In carrying out the above objects and other objects, the presentinvention provides a powered panel moving system for moving a panel. Thesystem includes a motor, electronic drive means, mechanical means,coupling means, and electronic anti-entrapment means which may all belocated within a housing. The drive means drives the motor in order torotate a rotor of the motor. The rotor has a rotational output inresponse to being driven. The mechanical means moves a panel upon beingdriven. The coupling means couples the rotational output of the rotor tothe mechanical means in order drive the mechanical means for themechanical means to move the panel. The anti-entrapment means controlsthe drive means to prevent the panel from entrapping an object. Thedrive means drives the motor based on measurement signals indicative ofat least one of motor current, motor speed, and panel position. Thedrive means and the anti-entrapment means are integrated with oneanother such that the anti-entrapment means controls the drive meansbased on the same measurement signals.

The drive means may include motor current sensing means operable toinfer a position of the rotor based on current of the motor. The drivemeans may include back emf sensing means on at least one motor phasecoil for inferring a position of the rotor based on back emf of themotor. The drive means may include impedance sensing means on at leastone motor phase coil for inferring a position of the rotor based onimpedance of the motor.

The motor may be a DC brush-less motor such as a stepper motor. The DCmotor preferably has a rated speed greater than 6,000 rpm. The drivemeans may include motor position sensing and indicating means forcounting motor pulses to determine the position of the rotor.

The coupling means may include rotational mechanical advantage means formatching speed and torque output of the rotor to a lower speed, highertorque output for the mechanical means to move the panel. The rotationalmechanical advantage means may include at least one gear meshed in agear train.

The motor may be mounted so as to move with the panel and the mechanicalmeans is mounted to a system in which the panel moves.

The mechanical means may include a flexible member to transmit torque orforce for driving the panel. The mechanical means may include at leastone of rack and pinion gearing, arm and sector gearing, planetarygearing, a worm gear, a toothed track or a slotted track for engagementwith a gear, a pneumatic piston, a hydraulic piston, and a gearboxtransmission. The mechanical means may include a clutching mechanism toenable engagement and disengagement of the motor to at least one of thecoupling means and the mechanical means. The mechanical means mayinclude a braking mechanism to lock the movement of the panel to adesired position upon the panel being in the desired position.

The moving of the panel may be about a hinged joint. The moving of thepanel may be at least one of a linear translation and a rotationaltranslation in a plane of the panel.

The anti-entrapment means may include analysis means operable with themotor current sensing means to determine presence of an obstruction tothe motion of the panel based on the current of the motor prior to thepanel applying destructive forces against the obstruction.

The anti-entrapment means may include analysis means operable fordetermining the presence of an obstruction to the motion of the panelbased on at least one of the rotor position, the motor current, and theback emf of the motor. The anti-entrapment means may be operable togenerate an indication of either end-of-travel of the panel or a motorstall condition based on at least one of the rotor position, the motorcurrent, and the back emf of the motor.

The anti-entrapment means may include powered panel control means. Theanti-entrapment means may include communication means for communicatingone or more indications from the powered panel moving system to anexternal unit including at least one of a controller that controls partof the operation of the moving system and an indication system forproviding an indication of a condition of the system.

The anti-entrapment means may include electronics for operating anobstruction detection sensor. The drive means and the anti-entrapmentmeans may be realized within a single integrated circuit.

The advantages associated with the powered panel moving system inaccordance with the present invention are numerous. For instance, thepowered panel moving system is cost competitive to existing low costpowered panel moving systems while providing improved obstructiondetection capability of more expensive powered panel moving systems.

Further, the powered panel moving system in accordance with the presentinvention provides a cost mitigation innovation for brush-lesselectronics as one aspect of the present invention. Other innovations ofthe powered panel moving system in accordance with the present inventionaddress acoustic and higher gear ratio issues.

BRIEF DESCRIPTION OF THE DRAWINGS

FIGS. 1 a, 1 b, and 1 c respectively illustrate representativemechanical and electrical configurations of two, three, and four phasesensor-based brush-less motors for use with a powered panel movingsystem in accordance with the present invention;

FIG. 2 a illustrates a variant of the two phase sensor-based brush-lessmotor shown in FIG. 1 a;

FIG. 2 b illustrates a variant of the four phase sensor-based brush-lessmotor shown in FIG. 1 c;

FIG. 3 a illustrates a further variant of the two phase sensor-basedbrush-less motor shown in FIG. 1 a;

FIG. 3 b illustrates a further variant of the four phase sensor-basedbrush-less motor shown in FIG. 1 c;

FIG. 4 illustrates a chart which summarizes functions of brush-lessmotor drive electronics, entrapment detection electronics, and poweredpanel control electronics which can be integrated with one another foruse with a powered panel moving system in accordance with the presentinvention;

FIG. 5 illustrates a block diagram of an exemplary powered panel movingsystem;

FIG. 6 illustrates a block diagram of a powered panel moving system inaccordance with the present invention;

FIGS. 7 a, 7 b, 7 c, and 7 d respectively illustrate different views ofan integrated motor assembly configuration for use with a powered panelmoving system in accordance with the present invention;

FIG. 8 illustrates a powered panel moving system having an integratedmotor assembly in accordance with the present invention; and

FIG. 9 illustrates a motor assembly configuration for use with a poweredpanel moving system in accordance with the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT(S)

In high duty cycle applications, the requirement to dissipate heat canlead to the use of a larger motor running at a lower speed than wouldotherwise be desired. In such a case it could be advantageous to use anexternal armature for improved heat dissipation to allow operation witha smaller motor in order to realize lower motor material cost, weight,and volume. However, this change requires the use of brush-lesselectronics which impose an increased cost although brush-less designsare more reliable by eliminating brush wear and failure.

Among other variations, brush-less motor electronics are provided intwo, three, and four phase variants with unipolar and bipolarexcitations. FIGS. 1 a, 1 b, and 1 c respectively illustraterepresentative mechanical and electrical configurations of two, three,and four phase sensor-based brush-less motors.

FIG. 1 a illustrates a mechanical and electrical configuration of atwo-phase sensor-based brush-less motor 10. Motor 10 includes a rotor 12and two stator segments 14 with armature windings 16 wrapped around thestator segments. Armature windings 16 electrically connect to brush-lessdrive electronics 18. Motor 10 represents a two-phase unipolar driveconfiguration. As such, drive electronics 18 includes one diode and onetransistor for each phase and position sensing, in this example a singlehall sensor H, to determine which armature phase to apply with current.

FIG. 1 b illustrates a mechanical and electrical configuration of athree-phase sensor-based brush-less motor 20. Motor 20 includes a rotor22 and three stator segments 24 with armature windings 26 wrapped aroundthe stator segments. Armature windings 26 electrically connect tobrush-less drive electronics 28. Motor 20 represents a three-phasebipolar drive configuration. For a bipolar drive, the drive electronicsincludes an extra set of diodes and transistors. As such, driveelectronics 28 includes two diodes and transistors per phase andposition sensing, in this example a rotary encoder 29, to determinewhich armature phase to apply with current.

FIG. 1 c illustrates a mechanical and electrical configuration of afour-phase sensor-based brush-less motor 30. Motor 30 includes a rotor32 and four stator segments 34 with armature windings 36 wrapped aroundthe stator segments. Armature windings 36 electrically connect tobrush-less drive electronics 38. Motor 30 represents a four-phasebipolar drive configuration. As with drive electronics 28 of thethree-phase motor 20 illustrated in FIG. 1 b, drive electronics 38includes two transistors and diodes per phase and position sensing forthe bipolar drive. In the example of FIG. 1 c, two Hall sensors h1, h2are used for position sensing.

In the configurations of motors 10, 30 illustrated in FIGS. 1 a and 1 c,position sensing is achieved with switched Hall sensors (H; h1, h2)whose signals are used to directly activate the drive transistors ofdrive electronics 18, 38 for the various motor phases. Although thisoffers cost advantages, this type of sensing can give as much as +/−30degrees of inaccuracy in the point at which a given armature phase isdriven. This can cause a loss of efficiency and power.

As shown in FIG. 2 a, with continual reference to FIG. 1 a, driveelectronics 18 of motor 10 includes a micro-controller 19 to process thesignals from analog Hall sensor H in a tracking mode in order to moreaccurately determine the position of rotor 12 and thereby provide moreoptimal switching to maximize motor efficiency and power. However, addedcircuitry in the form of micro-controller 19 adds costs to driveelectronics 18.

Likewise, as shown in FIG. 2 b, with continual reference to FIG. 1 c,drive electronics 38 of motor 30 includes a micro-controller 39 toprocess the signals from analog Hall sensors H1, H2 in a tracking modein order to more accurately determine the position of rotor 32 andthereby provide more optimal switching to maximize motor efficiency andpower. Again, however, added circuitry in the form of micro-controller39 adds costs to drive electronics 38.

Other sensor options include optical rotary encoders and resolvers suchas rotary encoder 29 of motor 20 shown in FIG. 1 b. Such rotary encodersand resolvers also impose cost penalties from the need for additionalcomponents and/or processing.

Motors 10, 20, 30 are shown respectively with two-pole rotors 12, 22,32. However, there are numerous applications with rotors having morethan two poles and there are numerous applications with rotors havingmore than four poles as well. In general, as either the number of rotorpoles or armature phases increases, the requisite position sensingaccuracy increases. Increased armature phases can also increase thecomplexity of the required switching drive electronics and logic.

An additional approach that can be taken in brush-less control is to usethe motor itself to provide the position determination. As shown in FIG.3 a, with continual reference to FIG. 2 a, micro-controller 19 of driveelectronics 18 receives sense signals taken from motor 10.Micro-controller 19 processes these signals to infer position of rotor12 of motor 10. Micro-controller 19 then selects the appropriate drivecomponents of drive electronics 18 which, in this case, is one of thetwo transistors in order to drive motor 10.

Likewise, as shown in FIG. 3 b, with continual reference to FIG. 2 b,micro-controller 39 of drive electronics 38 receives sense signals (S1,S2, S3, S4) taken from motor 30. Micro-controller 39 processes thesesignals to infer position of rotor 32 of motor 30. Micro-controller 39then selects the appropriate drive components (i.e., the transistors) ofdrive electronics 38 in order to drive motor 30.

Common methods used include (i) sensing the back emf from un-drivenphase coils and (ii) measuring phase impedance via brief sacrificialcurrent pulses and/or application of a low amplitude high-frequencysense signal. The high-frequency components in the motor drive voltageor current originating from the square or trapezoidal motor drivewaveforms could also be evaluated to infer impedance of the drivenphases. Another approach is to add additional sense coils in combinationwith back emf and/or impedance sensing.

Although these approaches offer advantages in terms of motor positionsensing accuracy and elimination of sensors they do have certainlimitations. Back emf sensing requires the rotor to be rotating orturning. Impedance sensing can add torque if sacrificial sensing pulsesare used or add expense if a high-frequency low-amplitude sense signalis applied. Additional sense coils are an added expense in and ofthemselves.

In powered panel applications such as automotive power windows, thepotential for entrapment and injury has lead to the employment ofsensors and electronics to detect entrapment and reverse the drive motorbefore serious injury occurs. One method of entrapment detection is tomonitor one or more motor parameters such as speed, drive voltage, andarmature current and/or to monitor panel parameters such as position andspeed as described in U.S. Pat. No. 6,064,165. Other methods ofobstruction detection include the employment of one or more additionalsensors to sense entrapment as described in U.S. Pub. No. 2003/0056600.These methods add expense and complexity to a power panel system byrequiring additional components and processing.

In general, the motion of a powered panel (i.e., a powered window) isslowed or halted upon entrapment. When this happens, any directmechanical linkage between the panel and a DC motor driving the panelslows motor rotation which in turn lowers the back emf of the motor.This generally results in increased current and torque. Entrapment canthen be inferred by either detecting the increase in motor current orthe decrease in motor or panel speed. In some applications, the nominalspeed of a powered panel and the associated motor back emf is positiondependent. This speed versus position variation can be a result of thefinite acceleration time at the start of travel and variations inresistance and mechanical advantage along the travel path of the panel.This motivates the use of position tracking as described in U.S. Pat.No. 6,064,165.

In simple entrapment detection, motor current is monitored andentrapment is inferred when the current exceeds a fixed threshold wherethe threshold matches the worst-case motor current draw during a normalpanel closure. In cases where there is indirect mechanical coupling tothe motor such as in pneumatic or hydraulic linkages, entrapmentdetection via detection of motor stalling or slowing may not bepossible.

Another simple method of entrapment detection is to detect for a drop inthe panel closing velocity below a predetermined threshold representingthe worst-case lowest velocity during panel closure. This may require aseparate speed sensor for the panel, especially where there is indirectmechanical linkage decoupling motor speed from panel speed.

A variation on these two simple entrapment detection methods is to inferentrapment from a rate of current increase or velocity decrease thatexceeds predetermined worst-case values. A complication to this is thelarge starting current at the beginning of travel and stall current anddrop in velocity at closure where in some cases it is necessary to drivea panel into a weather seal. This can lead to a requirement for absoluteposition detection and/or end-and-beginning of travel detection.Indirect mechanical linkages provide complications to this approach aswell as motor speed can be decoupled or non-linearly coupled to panelspeed.

Dedicated sensors and/or systems that can be employed for entrapmentdetection include proximity and touch sensors such as described in U.S.Pub. No. 2003/0056600, as well as optical and conductive sensors amongothers. As noted, these systems have the drawback of adding cost throughadding components as well as installation.

In a first aspect of the powered panel moving system in accordance withthe present invention, all or a portion of the entrapment detectionelectronics and processing is integrated with the drive electronics of abrush-less motor. A first advantage of this configuration is in terms ofsimplifying packaging and installation as a result of componentreduction and system simplification.

A second advantage of this configuration is that measurements such asmotor current, motor speed, and panel position that are used for bothmotor control and entrapment detection can be shared. This saves theexpense of duplicating these measurements in separate systems andprovides a value added for each function that is used twice. In thisway, the added expense of brush-less drive electronics is compensatedfor by the added functionality of entrapment detection that can berealized using measures and/or components common to both motor drivecontrol and entrapment detection.

For instance, a current measuring capability for sensor-less motorposition sensing via impedance measurement can also be used to providedrive current measurement for entrapment detection. Similarly, thederived motor position can be processed to provide estimates of motor orpanel speed, position, and acceleration. These, especially when combinedwith drive current sensing, can be used for entrapment detection.

A further aspect of the powered panel moving system in accordance withthe present invention is to integrate powered panel control electronicswith the brush-less motor drive electronics and/or with the entrapmentdetection electronics to form a combined power panel system. As anexample, powered panel control electronics includes electronics for“express open” and “express close” panel functions. As such, in responseto an operator pressing an express close button, the window closeswithout requiring the operator to continuously press the express closebutton.

Referring now to FIG. 4, a chart 40 generally summarizes functions ofbrush-less motor drive electronics 42, functions of entrapment detectionelectronics 44, and functions of powered panel control electronics 46that can be integrated with one another in accordance with the presentinvention. In general, brush-less motor control functions are carriedout by brush-less motor drive electronics 42, entrapment detectionfunctions are carried out by sensor drive electronics 44, and poweredpanel control functions are carried out by panel control electronics 46.As indicated, brush-less motor drive electronics 42, sensor driveelectronics 44, and panel control electronics 46 may be integrated withone another in various combinations to form a combined power panelsystem.

For example, block 47 lists common functions provided by brush-lessmotor drive electronics 42 and entrapment detection electronics 44 thatcan be used for brush-less motor control and entrapment detection. Block48 lists common functions provided by brush-less motor drive electronics42, entrapment detection electronics 44, and powered panel controlelectronics 46 that can be used for brush-less motor control, entrapmentdetection, and powered panel control. Block 49 lists common functionsprovided by entrapment detection electronics 44 and powered panelcontrol electronics 46 that can be used for entrapment detection andpowered panel control. Although no single controller would necessarilyuse all of these functions, many combinations are possible where atleast one of these functions would be common to brush-less driveelectronics 42 and entrapment detection electronics 44 and/or powerpanel control electronics 46.

In some powered panel applications, it may be desirable to employ asmaller motor to reduce material costs and/or to meet size and weightconstraints. However, as indicated above, a smaller motor runs at ahigher speed and at a lower torque to deliver the power of a largermotor. Increased motor speeds result in greater brush wear. As a result,the use of a smaller, faster motor leads to the requirement forbrush-less electronics. To recover the torque and panel driving forcedeveloped with a slower, larger motor, a high-speed motor must beconfigured with a higher mechanical advantage linkage than that usedwith the larger motor.

With reference to FIGS. 5 and 6, it is a further aspect of the presentinvention to provide a powered panel moving system which is configuredwith a high-speed brush-less DC motor driving a high mechanicaladvantage reduction gear system in order to produce the torque and speedcombination of a larger motor that would otherwise be required.

FIG. 5 illustrates a sample powered window moving system 50. System 50includes a large DC brush motor 52 which is associated with currentsensing and motor reversal electronic circuitry 55. As an example, brushmotor 52 operates at a motor speed of 3,000 rpm at 0.4 Nm torque. A 25:1planetary gear reduction 53 converts the 3,000 rpm motor speed at 0.4 Nmtorque to an output rotation of 120 rpm at 10 Nm for a 3,000/120=25:1torque multiplication and speed reduction. A rack and pinion gear 54converts the 120 rpm output to linear motion to drive a window with nearstall forces of 450 N or more and unobstructed speeds of 11 inch/sec ormore.

FIG. 6 illustrates a powered window moving system 60 in accordance withthe present invention. In general, system 60 is configured with a smallbrush-less DC motor 66 which drives a high mechanical advantage gearreduction system 67 to produce the torque and speed combination of abrush motor (such as large DC brush motor 52) that would otherwise beused. To this end, brush-less motor 66 operates at a motor speed of30,000 rpm at 0.04 Nm torque. A 250:1 planetary gear reduction 67converts the 30,000 rpm at 0.04 Nm torque to an output rotation of 120rpm at 10 Nm for a 30,000/120=250:1 torque multiplication and speedreduction. A rack and pinion gear 64 converts the 120 rpm output tolinear motion to drive a window with near stall forces of 450 N or moreand unobstructed speeds of 11 inch/sec or more. The cost savings theresulting reduction in motor materials (i.e., the cost savings betweensmall brush-less motor 66 and large brush motor 52) is then applied tooffset the cost of brush-less motor drive electronics 68.

Note that the specific speed and torque values in FIGS. 5 and 6 areprovided by way of example as being typical for an automotive powerwindow system. As such, other speed and torque combinations arepossible. Similarly, the rack and pinion and planetary gear mechanicalcoupling (64, 67; 54, 53) is shown by way of example. As such, othermechanical coupling configurations such as those already described arealso possible.

As shown in FIG. 6, powered window moving system 60 in accordance withthe present invention may further include a secondary obstruction sensoror sensing system 61. Secondary obstruction sensor 61 is placed in thevicinity of the window and is generally operable to detect the presenceof an object such as a human body part in the vicinity of the window. Assuch, secondary obstruction sensor 61 is generally operable to detectentrapment and possible entrapment of objects by the window. Secondaryobstruction sensor 61 may be in the form of a capacitance sensor such asdescribed in U.S. Pub. No. 2003/0056600. In this embodiment, a costsavings is realized in the employment of secondary obstruction sensor 61by integrating all or part of its electronics into brush-less motordrive electronics 68.

With reference to FIGS. 5 and 6, powered window moving system 60 inaccordance with the present invention is configured to have a cost andperformance advantage over existing moving systems by using a smallerlower cost (but lower torque and higher speed) brush-less motor 66 inplace of a larger brush motor such as large brush motor 52. Themechanical advantage mechanism 53 used with large brush motor 52 insystem 50 is replaced with a larger ratio mechanical advantage mechanism67 in system 60. The cost savings of smaller brush-less motor 66 is thenapplied to offset the cost of brush-less motor drive electronics 68.

Further, the position sensing of brush-less motor drive electronics 68is combined with additional soft obstruction detection electronics 69which provides detection methodology as described in U.S. Pat. No.6,064,165. Such detection methodology provided by obstruction detectionelectronics 69 senses obstructions via motor current sensing asdescribed in U.S. Pat. No. 6,064,165. As described, the detectionmethodology carried out by obstruction detection electronics 69 is doneby monitoring one or more motor parameters such as speed, drive voltage,and armature current and/or monitoring window parameters such asposition and speed in order to carry out position tracking.

Referring now to FIGS. 7 a, 7 b, 7 c, and 7 d, with continual referenceto FIG. 6, different views of an integrated motor assembly configuration70 in accordance with the present invention are shown. The integratedmotor assembly configuration has cost and performance advantages. Bothbrush type and brush-less motor designs can benefit from this integratedmotor assembly configuration. As shown in FIGS. 7 a, 7 b, 7 c, and 7 d,high-speed brush-less DC motor 66 integrates with a rack and pinion gear64 plus planetary gear mechanical coupling 67 for direct interface to adrive component 72.

Further visualization is provided in FIG. 8 which shows integrated motorassembly 70 as it might appear in a powered window moving system 80 inaccordance with the present invention. Integrated motor assembly 70interfaces to a cable drive component 72 to move a window 82 on astationary track 84. Integrated motor assembly 70 moves window 82 to afully closed position in which the window engages a weather sealprovided on a door frame 86. The simplified package captures allelectronics for processing entrapment detection, brush-less motorcontrol, and user functionality into integrated motor drive assembly 70.

A further embodiment of the powered panel moving system in accordancewith the present invention operates to eliminate noise and reliabilityissues related to reduction gearing. This is done by replacing thereduction gear with a torque converter incorporated within the motor bydirect attachment of an impeller pump to the rotor of the motor or ashaft from the rotor and direct attachment of a turbine to an outputshaft. A fluid or pneumatic coupling to the turbine is then used totransmit torque from the rotor to the output shaft connected to theturbine. This method can be applied to brushed motors, brush-lessmotors, and externally or internally wound armature AC or DC motors.

By way of example, FIG. 9 illustrates a realization of this embodimentof the present invention with a brush-less DC motor 90. In thisapproach, the conventional brush-less DC configuration of a permanentmagnet rotor 91 with electronically switched stator coils 92 is used.However, rotor 91 has no direct mechanical connection to an output shaftof the system. Instead, rotor 91 incorporates a fluid (or alternativelya pneumatic) impeller pump 93 that couples to an output turbine 94 via afluid (or alternatively a pneumatic) coupling 95. In this configurationof pump 93 with coupling 95 to turbine 94 there can be torquemultiplication of the torque delivered from the pump to the outputtorque of the turbine when the pump rotates faster than the turbine.

In brush-less DC motor 90, pump 93, turbine 94, and fluid channels aresized and shaped so as to provide an optimal coupling at a desired rangeof rotation ratio of pump rotation to turbine rotation over a desiredrange of pump speeds. These components are also sized and shaped so asto achieve a desired range of torque multiplication over a desired rangeof pump speeds with a desired range of pump to turbine speed ratios.Typically, the coupling is made most efficient at the rated speed andtorque of the motor when the turbine is at a preferred speed and torque.

Designing for specific rotation ratios and torque multiplications isreadily achieved by techniques available to those skilled in the art ofturbine design. Even at the designed operating point there will bemechanical efficiency losses to the fluid. If the output torque is notsufficient to drive the load of turbine 94, then the turbine rotationslows resulting in an increase in turbine torque in accordance with themanner of conventional fluid based torque converters as presentlyemployed in automotive drive train applications.

This approach of combining a motor (nominally brush-less DC) with afluid (or pneumatic) torque converter offers reliability, cost, andnoise advantages via the elimination of the complexity, mechanicalcontact, and wearing of reduction gearing. It also offers the advantageof a variable and self-matching mechanical advantage via the torquemultiplication behavior of the fluid coupling of appropriatelyconfigured pumps and turbines. This can provide significant outputtorque at low speeds and/or at start-up without significantly increasingthe mechanical load on the motor.

This offers a further advantage in being able to increase torque withouthaving the motor draw significantly more current as would be the casewith a fixed ratio gear train. It also allows the motor to operate nearits rated speed so as to maximize its power input to the fluid. In fixedratio couplings such as a gear train, an increased torque loadnecessarily slows the motor taking it away from its rated speed wherethe power delivered to the rotor necessarily drops. With a fluidcoupling the increased torque load does not slow the motor.

A disadvantage is that the fluid coupling may not be as mechanicallyefficient as a gear train. This inefficiency can force the motor size ordrive current to be increased to compensate for the loss of power. Afurther disadvantage is that the lost power goes into heat in the torqueconverter. However, for intermittent as opposed to continuous operationsuch as is seen in power window systems, the heating is not a concern.Similarly, in applications where sufficient heat sinking can be providedthe heating is not a concern. As there is no direct mechanical couplingbetween the motor and the turbine, it may be necessary to incorporate amechanical brake or lock to hold the window in position after the motorstops turning.

Also, in more advanced applications where motor speed control isavailable; the fluid coupling could be intermittently bypassed by use ofan inline clutching mechanism to mechanically lock the motion of therotor to that of the turbine in a fixed speed ratio. The clutch would bedisengaged for motor launch or when there was an increase in torquedemand that slows the motor unacceptably from its rated speed.Additional salient features of this approach are that to the extent thatthe rotor and turbine can be kept within the same housing 96, the numberof moving parts and mechanical connections can be minimized. Further, ifthe design allows the fluid to contact all or part of the rotor, theheat sinking of the rotor can be improved. This could be of particularadvantage if the armature windings are on the rotor. The use of journalbearings 98 on both ends of rotor 91 and one end of turbine 94 allowsthese bearings to be isolated from any outside contaminants and, ifdesired, be lubricated by the fluid itself. An additional designconsideration is to keep high pressure or rapidly moving fluid away fromthe region of the non-journal turbine bearing.

While embodiments of the present invention have been illustrated anddescribed, it is not intended that these embodiments illustrate anddescribe all possible forms of the present invention. Rather, the wordsused in the specification are words of description rather thanlimitation, and it is understood that various changes may be madewithout departing from the spirit and scope of the present invention.

1. A powered panel moving system for moving a panel, the systemcomprising: a motor having a rotor; electronic drive means for drivingthe motor in order to rotate the rotor, wherein the rotor has arotational output in response to being driven; mechanical means formoving a panel upon being driven; coupling means for coupling therotational output of the rotor to the mechanical means in order drivethe mechanical means for the mechanical means to move the panel; andelectronic anti-entrapment means for controlling the drive means toprevent the panel from entrapping an object; wherein the drive meansdrives the motor based on measurement signals indicative of at least oneof motor current, motor speed, and panel position, wherein the drivemeans and the anti-entrapment means are integrated with one another suchthat the anti-entrapment means controls the drive means based on thesame measurement signals.
 2. The system of claim 1 wherein: the drivemeans includes motor current sensing means operable to infer a positionof the rotor based on current of the motor.
 3. The system of claim 1wherein: the motor includes at least one motor phase coil; wherein thedrive means includes back emf sensing means on the least one motor phasecoil, wherein the back emf sensing means is operable to infer a positionof the rotor based on back emf of the motor.
 4. The system of claim 1wherein: the motor includes at least one motor phase coil; wherein thedrive means includes impedance sensing means on the at least one motorphase coil, wherein the impedance sensing means is operable to infer aposition of the rotor based on impedance of the motor.
 5. The system ofclaim 1 wherein: the motor is a DC brush-less motor; wherein the drivemeans includes motor position sensing and indicating means.
 6. Thesystem of claim 5 wherein: the DC brush-less motor is a stepper motor;wherein the motor position sensing and indicating means counts motorpulses to determine the position of the rotor.
 7. The system of claim 1wherein: the coupling means includes rotational mechanical advantagemeans for matching speed and torque output of the rotor to a lowerspeed, higher torque output for the mechanical means to move the panel,wherein the rotational mechanical advantage means includes at least onegear meshed in a gear train.
 8. The system of claim 1 wherein: the motoris mounted so as to move with the panel and the mechanical means ismounted to a system in which the panel moves.
 9. The system of claim 1wherein: the mechanical means includes a flexible member to transmittorque or force for driving the panel.
 10. The system of claim 1wherein: the mechanical means includes at least one of rack and piniongearing, arm and sector gearing, planetary gearing, a worm gear, atoothed track or a slotted track for engagement with a gear, a pneumaticpiston, a hydraulic piston, and a gearbox transmission.
 11. The systemof claim 1 wherein: the mechanical means includes a clutching mechanismto enable engagement and disengagement of the motor to at least one ofthe coupling means and the mechanical means, the mechanical meansfurther includes a braking mechanism to lock the movement of the panelto a desired position upon the panel being in the desired position. 12.The system of claim 1 wherein: the moving of the panel is about a hingedjoint.
 13. The system of claim 1 wherein: the moving of the panel is atleast one of a linear translation and a rotational translation in aplane of the panel.
 14. The system of claim 2 wherein: theanti-entrapment means includes analysis means operable with the motorcurrent sensing means to determine presence of an obstruction to themotion of the panel based on the current of the motor prior to the panelapplying destructive forces against the obstruction.
 15. The system ofclaim 2 wherein: the anti-entrapment means includes analysis meansoperable for determining the presence of an obstruction to the motion ofthe panel based on at least one of the rotor position and the motorcurrent.
 16. The system of claim 3 wherein: the anti-entrapment meansincludes analysis means operable for determining the presence of anobstruction to the motion of the panel based on at least one of therotor position and the back emf of the motor.
 17. The system of claim 2wherein: the anti-entrapment means is operable with the motor currentsensing means to generate an indication of end-of-travel of the panelbased on at least one of the rotor position and the motor current. 18.The system of claim 3 wherein: the anti-entrapment means is operablewith the back emf sensing means to generate an indication ofend-of-travel of the panel based on at least one of the rotor positionmotor and the back emf of the motor.
 19. The system of claim 2 wherein:the anti-entrapment means is operable with the motor current sensingmeans to generate an indication of a motor stall condition based on atleast one of the rotor position and the motor current.
 20. The system ofclaim 3 wherein: the anti-entrapment means is operable with the back emfsensing means to generate an indication of a motor stall condition basedon at least one of the rotor position and the back emf of the motor. 21.The system of claim 1 wherein: the anti-entrapment means includespowered panel control means.
 22. The system of claim 1 wherein: theanti-entrapment means includes communication means for communicating oneor more indications from the powered panel moving system to an externalunit, wherein the external unit includes at least one of a controllerthat controls part of the operation of the moving system and anindication system for providing an indication of a condition of thesystem.
 23. The system of claim 1 wherein: the anti-entrapment meansincludes electronics for operating an obstruction detection sensor. 24.The system of claim 5 wherein: the DC motor has a rated speed greaterthan 6,000 rpm.
 25. The system of claim 1 wherein: the drive means andthe anti-entrapment means are realized within a single integratedcircuit.